Mark ob_*() functions has side-effects

[zonuexe]

resolve phpstan/phpstan#12577

All ob_*() functions are impure.

It's possible to implement state like clearstatcache() in scopes, but it probably makes sense to just mark these as ['hasSideEffects' => true] and leave it at that.

[ondrejmirtes]

Please follow instructions here

phpstan-src/resources/functionMetadata.php

Lines 3 to 15 in 2fe4e0f

	/**
	* GENERATED FILE - DO NOT EDIT!
	*
	* This file is generated automatically when running bin/generate-function-metadata.php
	* and the result is merged from bin/functionMetadata_original.php and by looking at jetbrains/phpstorm-stubs methods
	* and functions with the #[Pure] attribute.
	*
	* If you want to add new entries here follow these steps:
	* 1) verify on https://phpstan.org/try whether the entry you are going to add does not already work as expected.
	* 2) Contribute the functions that have 'hasSideEffects' => true as a modification to bin/functionMetadata_original.php.
	* 3) Contribute the #[Pure] functions without side effects to https://github.com/JetBrains/phpstorm-stubs
	* 4) Once the PR from 3) is merged, please update the package here and run ./bin/generate-function-metadata.php.
	*/

[zonuexe]

@ondrejmirtes

The PhpStorm stub marks ob_get_contents() as follows:

#[Pure(true)]
function ob_get_contents(): string|false {}

#[Pure(true)] is defined as follows:

class Pure
{
    /**
     * @param bool $mayDependOnGlobalScope Whether the function result may be dependendent on anything except passed variables
     */
    public function __construct(bool $mayDependOnGlobalScope = false)
    {
    }
}

ob_get_contents() is clearly an impure function with state, but it doesn't make sense to write ob_get_contents(); on a separate line. #[Pure(true)] means that.

This is the same as the #2037 vs 2b5b317 conflict about file_get_contents().

According to the current semantics of PHPStan, all #[Pure(true)] should be declared as hasSideEffects => true, but importing them all seems to break many of PHPStan's tests.

[ondrejmirtes]

Not needed anymore thanks to #3880